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A STUDY ON ECONOMY EVALUATION ON THE PROFIT AND LOSS OF GEOLOGIC ENVIRONMENTAL QUALITY ABOUT GEOLOGIC ENVIRONMENTAL EXPLOITATION PROJECT
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《石家庄经济学院学报》 1995年第S1期106-109,共4页
The problems of environmental geology refer to the geologic phenomena, incidents or accidents arising from action of environmental geology. The action is mainly the mutual influence between human activity and geologic... The problems of environmental geology refer to the geologic phenomena, incidents or accidents arising from action of environmental geology. The action is mainly the mutual influence between human activity and geologic environment. When human activity is uncoordinated with objective laws of the geologic environment, the problems of environmental geology or economic loss would occur.Therefore,the level and the changing orientation of geologic environmental quality are relative to the types of human activity,particularly relative to human intentional-activities of geologic environmental exploitation project. The geologic environment fitting to mining may not fit to urban construction,and fitting to water conservancy and hydroelectric projects may not fit to communication,and so on.Economy evaluation on the profit and loss of geologic environmental quality is exactly to depict the level of the profit and loss of geologic environmental quality about geologic environmental exploitation projects and the 展开更多
关键词 TH A STUDY ON ECONOMY EVALUATION ON the PRofIT AND loss of GEOLOGIC ENVIRONMENTAL QUALITY ABOUT GEOLOGIC ENVIRONMENTAL EXPLOITATION project
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Key issues in rock mechanics of the Three Gorges Project in China 被引量:2
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作者 Qixiang Fan Hongbing Zhu Xuchun Chen 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE 2011年第4期329-342,共14页
The Three Gorges Project is one of the essential key projects for flood controlling and water resources regulation in the Yangtze River. The project includes a river-crossing dam, underground powerhouses, and navigati... The Three Gorges Project is one of the essential key projects for flood controlling and water resources regulation in the Yangtze River. The project includes a river-crossing dam, underground powerhouses, and navigation structures. Because of the huge size and complicated construction technologies, the project faced a series of challenging engineering issues. In terms of rock mechanics, there are many key technical issues, including the sliding resistance and stability of the dam section along the foundations of powerhouses No.l-5, the ,,;lope stability of the double-line five-stage shiplock, excavation of large-scale underground powerhouses, and curtain grouting under the dam. With decades of scientific research and 16 years of practical construction experiences and reservoir operations, these key technical issues in construction of the Three Gorges Project are successfully resolved, which will attribute to the development of hydropower technology. On the basis of the monitoring data during construction and normal operation periods of the Three Gorges Project, this paper presents a systematic analysis of these key rock mechanical issues in terms of behaviors, solutions, dynamic controlling, monitoring arrangement and integrated assessment. 展开更多
关键词 Three Gorges project rock mechanics dam sliding resistance and stability high shiplock slope undergroundpowerhouses curtain grouting
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Fluid-solid interaction of resistance loss of flexible hose in deep ocean mining 被引量:3
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作者 王志 饶秋华 刘少军 《Journal of Central South University》 SCIE EI CAS 2012年第11期3188-3193,共6页
The resistance loss of transportation was studied and the influences of buoyancy layout,mineral content and elastic modulus of flexible hose were investigated based on three-dimensional finite element model of fluid-s... The resistance loss of transportation was studied and the influences of buoyancy layout,mineral content and elastic modulus of flexible hose were investigated based on three-dimensional finite element model of fluid-solid interaction by MSC.MARC/MENTAT software.The numerical results show that the resistance losses increase with the increase of mineral content Cv and velocity of internal fluid v and decrease with the increase of elastic modulus E of flexible hose.The buoyancy layout and the velocity of internal fluid have greater impacts on the resistance losses than the elastic modulus of flexible hose.In order to reduce the resistance losses and improve the efficiency of the deep-ocean mining,Cv and v must be restricted in a suitable range (e.g.10%-25% and 2.5-4 m/s).Effective buoyancy layout (such as Scheme C and D) should be adopted and the suitable material of moderate E should be used for the flexible hose in deep-ocean mining. 展开更多
关键词 resistance loss flexible hose fluid-solid interaction deep-ocean mining finite element method
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The Abrasion-resistance Investigation of Rubberized Concrete 被引量:1
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作者 亢景付 ZHANG Bo LI Guangu 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2012年第6期1144-1148,共5页
The abrasion resistance properties of rubberized concrete were comparatively studied by taking silica fume and crumb tire rubber as the additives. The abrasion tests were conducted in accordance with the Chinese stand... The abrasion resistance properties of rubberized concrete were comparatively studied by taking silica fume and crumb tire rubber as the additives. The abrasion tests were conducted in accordance with the Chinese standard test method DL/T 5150 - 2001, two recommended test methods: under water method and ring method, were used. The crumb tire rubbers with the sieve size of 8-mesh and 16-mesh were incorporated into the concrete by replacing same volume of sand and as an additive. The abrasion resistance of concrete was evaluated according to the abrasion resistance strength and the mass loss. Test results show that the addition of silica fume enhanced both compressive strength and abrasion resistance of concrete, and the addition of crumb rubber reduced the compressive strength but increased notably the abrasion resistance of the concrete. Silica fume concrete performed a better abrasion resistance than control concrete, and the rubberized concrete performed a much better abrasion resistance than silica fume concrete. The abrasion resistance of rubberized concrete increased with the increase of rubber content. 展开更多
关键词 abrasion resistance silica fume concrete rubberized concrete mass loss
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Resistance Analysis of 25 Corn Varieties to Stalk Rot and Evaluation of Yield Loss 被引量:1
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作者 Wang Liangfa Wang Yaochuang +3 位作者 Zhang Sujuan Zhu Zikuan Zhang Huiyu Zhang Shoulin 《Plant Diseases and Pests》 CAS 2016年第5期16-20,共5页
Due to the meteorological factors, Henan Province had a large-scale outbreak of corn stalk rot in 2014, and the incidence status of 25 varieties was investigated. According to the relevant resistance identification st... Due to the meteorological factors, Henan Province had a large-scale outbreak of corn stalk rot in 2014, and the incidence status of 25 varieties was investigated. According to the relevant resistance identification standards, Xundan.509 was classified as resistance variety; Yudan606, Jinsai38 and Xundan3136 were classified as moderate resistance ones, while the other 21 varieties were highly susceptible varieties. Using the yield loss rate of 5% as the critical value of disease tolerance standard, XundanS09, Yudan606, Jinsai38, Xundan3136, Huaiyu5288, QiaoyuS, XY046, Zhengyu10, Lile66, WeikeT02 and Xundan29 were classified into tolerance varieties of corn stalk rot. The concept between disease resistance and disease tolerance was distinguished. The diseased plant rate was used as the classification basis of disease resistance and the yield loss rate was used as the evaluation standard of disease tolerance. The relationship between both was showed by a Venn diagram. 展开更多
关键词 CORN Stalk rot Yield loss rate Disease resistance Disease tolerance
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The AC losses measurement and analysis of superconducting NbTi CICC for HT-TU superconducting Tokamak 被引量:8
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作者 FANG Jin +2 位作者 WENG Pei-De 《Nuclear Science and Techniques》 SCIE CAS CSCD 2003年第1期76-82,共7页
Superconducting TF and PF coils have been measured in SULTAN test facility. Segregated copper strands are included in four NbTi CICC and this is a technical innovation. Two AC losses measurement methods, calorimetric ... Superconducting TF and PF coils have been measured in SULTAN test facility. Segregated copper strands are included in four NbTi CICC and this is a technical innovation. Two AC losses measurement methods, calorimetric and electromagnetic methods, have been used in the experiments, and a broad frequency range (from 0.05 Hz to 6 Hz) is covered in sample test. The purpose of this experiment was to investigate AC losses of TF and PF CICC conductor including segregated copper and to check the design of PF and TF CICC coated with different resistive barriers (Pb-30Sn-2Sb and Ni plating on NbTi strands). 展开更多
关键词 HT-7U 超导托卡马克装置 CICC 超导体 铌钛合金 线圈 直流损耗 测量
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Effect of molecular structure and slump loss resistance of polycarboxylate superplasticizers on self-compacting concrete
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作者 兰自栋 《Journal of Chongqing University》 CAS 2016年第1期35-42,共8页
A new kind of polycarboxylate superplasticizer with high slump loss resistance was obtained by designing scheduled molecular structure.The number average molecular mass of the polymer was characterized by the gel perm... A new kind of polycarboxylate superplasticizer with high slump loss resistance was obtained by designing scheduled molecular structure.The number average molecular mass of the polymer was characterized by the gel permeation chromatography measurements.And chemical structure of the polymer was observed by the Fourier transform infrared spectroscopy(FT-IR).The results show that the good workable maintaining of self-compacting concrete could be achieved through direct adjustment of number average molecular mass and different unsaturated monomer in synthetic process.The FT-IR analysis illustrated that the high slump loss resistance of polycarboxylate superplasticizers with ester and carboxyl group and expectations of molecular structure were designed. 展开更多
关键词 high slump loss resistance of polycarboxylate superplasticizers self-compacting concrete number average molecular mass WORKABILITY
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Stalk Rot Resistance Analysis and Yield Loss Evaluation on 25 Maize Varieties and Utilization of Resistant Germplasm Jun M9
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作者 Ruiqian LU Hailei JIN +3 位作者 Shoulin ZHANG Jinkui ZHANG Changjian LI Zhifang ZHANG 《Agricultural Biotechnology》 CAS 2018年第6期41-45,共5页
Stalk rot outbroke in Henan Province in 2014 on maize,and the disease conditions of 25 varieties were investigated.According to national maize variety disease resistance identification standards,Jundan 509 was a resis... Stalk rot outbroke in Henan Province in 2014 on maize,and the disease conditions of 25 varieties were investigated.According to national maize variety disease resistance identification standards,Jundan 509 was a resistant variety; Yudan 606,Jinsai 38 and Jundan 3136 were moderately-resistant varieties; and other 21 varieties were all highly susceptible.Based on the yield loss rate of 5% determined as the critical value for division of disease tolerance,disease-tolerant varieties included Jundan 509,Yudan 606,Jinsai 38,Jundan 3136,Huaiyu 5288,Qiaoyu 8,XY046,Zhengyu 10,lile 66,weike 702 and Jundan 29.Varietal disease resistance and tolerance were mainly divided according to incidence and yield loss rate,respectively,and the correlation between them was showed by a Venn diagram.With the male parent Jun M9 of Jundan 509 as a backbone material,multiple maize combinations resistant to stalk rot were formed,and Yongyou 618 among them was approved by Henan Provincial Crop Variety Approval Committee. 展开更多
关键词 MAIZE VARIETY STALK ROT loss rate of yield DISEASE resistance DISEASE tolerance
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Fast forward modeling of muon transmission tomography based on model voxelization ray energy loss projection
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作者 Zhang Rong-Qing Xi Zhen-Zhu +2 位作者 Liu Wei Wang He Yang Zi-Yan 《Applied Geophysics》 SCIE CSCD 2022年第3期395-408,471,共15页
To solve the problems associated with low resolution and high computational effort infinite time,this paper proposes a fast forward modeling method for muon energy loss transmission tomography based on a model voxeliza... To solve the problems associated with low resolution and high computational effort infinite time,this paper proposes a fast forward modeling method for muon energy loss transmission tomography based on a model voxelization energy loss projection algorithm.First,the energy loss equation for muon transmission tomography is derived from the Bethe–Bloch formula,and the imaging region is then dissected into several units using the model voxelization method.Thereafter,the three-dimensional(3-D)imaging model is discretized into parallel and equally spaced two-dimensional(2-D)slices using the model layering method to realize a dimensional reduction of the 3-D volume data and accelerate the forward calculation speed.Subsequently,the muon energy loss transmission tomography equation is discretized using the ray energy loss projection method to establish a set of energy loss equations for the muon penetration voxel model.Finally,the muon energy loss values at the outgoing point are obtained by solving the projection coefficient matrix of the ray length-weighted model,achieving a significant reduction in the number of muons and improving the computational efficiency.A comparison of our results with the simulation results based on the Monte Carlo method verifies the accuracy and effectiveness of the algorithm proposed in this paper.The metallic mineral identification tests show that the proposed algorithm can quickly identify high-density metallic minerals.The muon energy loss response can accurately identify the boundary of the anomalies and their spatial distribution characteristics. 展开更多
关键词 Muon transmission tomography model voxelization ray energy loss projection fast forward modeling Monte Carlo simulation
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Moisture Absorption, Mass Loss and Evaporative Resistance of Clothing in Transient Condition
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作者 Chuansi Gao Ingvar Holmr 《Journal of Donghua University(English Edition)》 EI CAS 2006年第5期54-58,共5页
The water vapour resistance of clothing ensembles is not as commonly determined as dry thermal insulation. The measurement techniques are more complicated and the measurement values differ among laboratories. Due to c... The water vapour resistance of clothing ensembles is not as commonly determined as dry thermal insulation. The measurement techniques are more complicated and the measurement values differ among laboratories. Due to complicated moisture transfer process through clothing ensemble, the moisture absorbed and evaporated varies in transient and steady state phases depending on properties, thickness of clothing, and environmental conditions. The purpose of this study was to measure moisture gain inside hygroscopic underwear, and hydrophobic and permeable outer wear as a function of time, to investigate mass loss from "skin" as well as from the manikin, to quantify evaporative heat loss and total heat loss from the manikin, and to determine water vaponr resistance of clothing. Manikin Tore was used by wearing wet "skin" to simulate sweating condition. Moisture content in the inner garment gain shows an exponential relation against time. Moisture in the outer permeable layer shows little gain. On the contrary, mass loss directly from the wet skin decreases exponentially. The mass loss from the manikin is relatively stable throughout three test phases. The evaporative heat loss is about 2/3 of the total heat loss from the sweating manikin. While measuring the evaporative resistance of clothing ensembles with hygroscopic inner garment and permeable outer garment, unlike to measure ensembles with impermeable outer layer, one hour measurement time is enough to get relatively stable results. The variation between the 1^rt hour and the 3^nd hour is less than 5%. The length of transient period and measurement time is dependent on the permeability, thickness of clothing ensembles and environmental conditions. 展开更多
关键词 moisture absorption mass loss evaporative resistance transient condition clothing ensemble.
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Low working loss Si/4H-SiC heterojunction MOSFET with analysis of the gate-controlled tunneling effect
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作者 Hang Chen You-Run Zhang 《Journal of Electronic Science and Technology》 EI CSCD 2023年第4期35-47,共13页
A silicon (Si)/silicon carbide (4H-SiC) heterojunction double-trench metal-oxide-semiconductor field effect transistor (MOSFET) (HDT-MOS) with the gate-controlled tunneling effect is proposed for the first time based ... A silicon (Si)/silicon carbide (4H-SiC) heterojunction double-trench metal-oxide-semiconductor field effect transistor (MOSFET) (HDT-MOS) with the gate-controlled tunneling effect is proposed for the first time based on simulations. In this structure, the channel regions are made of Si to take advantage of its high channel mobility and carrier density. The voltage-withstanding region is made of 4H-SiC so that HDT-MOS has a high breakdown voltage (BV) similar to pure 4H-SiC double-trench MOSFETs (DT-MOSs). The gate-controlled tunneling effect indicates that the gate voltage (V_(G)) has a remarkable influence on the tunneling current of the heterojunction. The accumulation layer formed with positive VG can reduce the width of the Si/SiC heterointerface barrier, similar to the heavily doped region in an Ohmic contact. This narrower barrier is easier for electrons to tunnel through, resulting in a lower heterointerface resistance. Thus, with similar BV (approximately 1770 V), the specific on-state resistance (R_(ON-SP)) of HDT-MOS is reduced by 0.77 mΩ·cm^(2) compared with that of DT-MOS. The gate-to-drain charge (Q_(GD)) and switching loss of HDT-MOS are 52.14% and 22.59% lower than those of DT-MOS, respectively, due to the lower gate platform voltage (V_(GP)) and the corresponding smaller variation (ΔV_(GP)). The figure of merit (Q_(GD)×R_(ON-SP)) of HDT-MOS decreases by 61.25%. Moreover, the heterointerface charges can reduce RON-SP of HDT-MOS due to trap-assisted tunneling while the heterointerface traps show the opposite effect. Therefore, the HDT-MOS structure can significantly reduce the working loss of SiC MOSFET, leading to a lower temperature rise when the devices are applied in the system. 展开更多
关键词 HETEROJUNCTION On-state resistance Silicon carbide(4H-SiC)trench metal-oxide-semiconductor field effect transistors(MOSFETs) Switching loss
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Sensorineural Hearing Loss in Multidrug-Resistant Tuberculosis Patients in Kinshasa (Democratic Republic of Congo): Prospective Cohort Study of Therapeutic Regimen with Aminoglycoside versus Bedaquiline
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作者 Mireille A. Mpwate Eddy M. Mbambu +11 位作者 Christian N. Matanda Gabriel M. Lema Michel K. Kaswa Murielle L. Aloni Nicole M. Anshambi Fabrice M. Matuta Luc L. Lukasu Dominique M. Mupepe Serge K. Mpwate Pierre Z. Akilimali Zacharie M. Kashongwe Richard N. Matanda 《Journal of Tuberculosis Research》 2023年第3期109-119,共11页
Context: Multidrug-resistant tuberculosis (MDR-TB) remains a major public health problem in developing countries such as the Democratic Republic of Congo (DRC), which continues to face the emergence of MDR-TB cases. B... Context: Multidrug-resistant tuberculosis (MDR-TB) remains a major public health problem in developing countries such as the Democratic Republic of Congo (DRC), which continues to face the emergence of MDR-TB cases. Because of the ototoxic effects of AGs, the World Health Organization (WHO) has recommended the introduction of the bedaquiline regimen. However, very few data are available regarding the susceptibility of bedaquiline to induce hearing loss, hence the present study set out to compare the AG-based regimen and the bedaquiline-based regimen in the occurrence of hearing loss in MDR-TB patients. Methods: This is a prospective multicenter cohort study that included 335 MDR-TB patients, performed in Kinshasa (DRC) during the period from January 2020 to January 2021. Sociodemographic, clinical, biological and audiometric data were analyzed using Stata 17. Repeated-measures analysis of variance was used to compare changes in the degree of hearing loss over time between the two groups of patients on AG and bedaquiline regimens. The double-difference method was estimated using regression with fixed-effects. A p value < 0.05 was considered the threshold for statistical significance. Results: The degree of hearing loss was similar between the two groups at the first month [AGs (28 dB) vs BDQ (30 dB);p = 0.298]. At six months, the mean degree of hearing loss was significantly greater in the aminoglycoside regimen group [AGs (60.5 dB) vs BDQ (44 dB);p < 0.001]. The double difference was significant, with a greater increase in hearing loss in the AGs group (diff-in-diff 18.3;p < 0.001). After adjustment for age and serum albumin, the group receiving the AG-based regimen had a 2-point greater worsening than those with bedaquiline at the sixth month (diff-in-diff 19.8;p Conclusion: Hearing loss is frequent with both treatment regimens, but more marked with the Aminoglycoside-based regimen. Thus, bedaquiline should also benefit for audiometric monitoring in future MDR-TB patients. 展开更多
关键词 Multidrug-Resistant Tuberculosis AMINOGLYCOSIDES Bedaquiline Hearing loss
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Determinants of the Sensorineural Hearing Loss in Patients with Multidrug-Resistant Tuberculosis in Kinshasa (Democratic Republic of the Congo): A Prospective Cohort Study
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作者 Mireille Avilaw Mpwate Eddy Mampuya Mbambu +13 位作者 Gabriel Mabuaka Lema Christian Nzanza Matanda Dominique Mayuku Mupepe Michel Kayomo Kaswa Murielle Luengiladio Aloni Nicole Muzutie Anshambi Fabrice Mankangu Matuta Luc Losenga Lukasu Serge Katya Mpwate Pierre Zalagile Akilimali Innocent Murhula Kashongwe Zacharie Munogolo Kashongwe Jean Marie Ntumba Kayembe Richard Nzanza Matanda 《International Journal of Otolaryngology and Head & Neck Surgery》 2023年第6期411-425,共15页
Background: The onset of the hearing loss is a major challenge during the treatment of multidrug-resistant tuberculosis (MDR-TB). Aminoglycoside-based regimens, to a lesser extent based on bedaquiline, induce ototoxic... Background: The onset of the hearing loss is a major challenge during the treatment of multidrug-resistant tuberculosis (MDR-TB). Aminoglycoside-based regimens, to a lesser extent based on bedaquiline, induce ototoxic sensorineural hearing loss. Research on risk factors is essential to enable high-risk individuals to benefit from preventive measures in settings with limited resources. Objective: This study aimed to assess the determinants of the hearing loss in patients with MDR-TB. Methods: This prospective multicenter cohort study included 337 patients with MDR-TB. It was performed in Kinshasa (Democratic Republic of the Congo) between January 2020 and January 2021. Sociodemographic, clinical, biological, therapeutic, and audiometric data were exported and analyzed using Stata 17 and MedCalc. The fixed-effect linear regression panel model was used to assess the degree of the hearing loss over time according to the following covariates: therapeutic regimen (aminoglycosides, bedaquiline, or alternate), stage of chronic kidney disease (CKD), age at inclusion, body mass index, serum albumin level, HIV status, alcohol intake, hypertension, and hemoglobin level. The Hausman test was used to select between fixed- and random-effect estimators. The threshold for statistical significance was set at p Result: A total of 236 patients (70%) received an aminoglycoside-based regimen, 61 (18%) received a bedaquiline-based regimen, and 40 (12%) received aminoglycosides relayed by bedaquiline. The frequency of the hearing loss increased from 62% to 96.3% within six months for all therapeutic regimens. The Hearing loss worsened, with moderate (72.4%) and profound (16%) deafness being predominant. An Exposure to the treatment for more than one month (β coeff: 27.695, Se: 0.793, p β coeff: 6.102, Se: 1.779, p β coeff: 5.610, Se: 1.682, p = 0.001), and an eGFR β coeff: 6.730, Se: 2.70, p = 0.013) were the independent risk factors associated with the hearing loss in patients with MDR-TB. Conclusions: The Hearing loss was more prevalent and worsened during the treatment of the patients with MDR-TB. An Exposure for more than one month, AG-based regimens, advanced age, hypoalbuminemia, and CKD have emerged as the main determinants of the worsening of the hearing loss. 展开更多
关键词 Multidrug-Resistant Tuberculosis Determinants Hearing loss DRC
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Assessment of Rice Cultivars in China for Field Resistance to Aphelenchoides besseyi 被引量:6
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作者 FENG Hui WEI Li-hui +1 位作者 LIN Mao-song ZHOU Yi-jun 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2014年第10期2221-2228,共8页
The effect ofAphelenchoides besseyi on 27 cultivars of rice (23japonica and 4 indica) was assessed in the field for two seasons during 2010 and 2011. The vigorous pathogenic nematodes culturing on Botrytis cinerea w... The effect ofAphelenchoides besseyi on 27 cultivars of rice (23japonica and 4 indica) was assessed in the field for two seasons during 2010 and 2011. The vigorous pathogenic nematodes culturing on Botrytis cinerea were used for this experiment. Inoculation was carried out at the tilling stage; the growth parameters and nematode population were recorded at the end of growth of rice plants. The results showed that the cultivars differed in their response to infection. Most of cultivars were lack of the characteristic symptom of white tip, which was seen less frequently than the other two symptoms, namely small grains and erect panicles; moreover, the expression of symptoms was probably hereditary. The infection lowered the values of all the measured biological parameters, namely length of the stem and of the panicle, the number of filled grains per panicle, and 100-grain weight, in all the cultivars. The final nematode population indicated that the threshold of economic damage had also been exceeded in 10 cultivars, and none of them was immune. Three japonica cultivars proved most vulnerable whereas Tetep, an indica type, showed a level of resistance potentially useful in controlling A. besseyi. 展开更多
关键词 Aphelenchoides besseyi RICE symptom expression yield loss resistance assessment
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Power losses caused by longitudinal HOMs in 1.3-GHz cryomodule of SHINE 被引量:4
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作者 Jun-Jie Guo Qiang Gu +2 位作者 Meng Zhang Zhen Wang Jian-Hao Tan 《Nuclear Science and Techniques》 SCIE CAS CSCD 2019年第7期16-26,共11页
Shanghai high-repetition-rate XFEL and extreme light facility (SHINE), the first hard XFEL based on a superconducting accelerated structure in China, is now under development at the Shanghai Institute of Applied Physi... Shanghai high-repetition-rate XFEL and extreme light facility (SHINE), the first hard XFEL based on a superconducting accelerated structure in China, is now under development at the Shanghai Institute of Applied Physics, Chinese Academy of Sciences. In this paper, power losses caused by trapped longitudinal high-order modes (HOM), steady-state loss, and transient loss generated by untrapped HOMs in the 1.3-GHz SHINE cryomodule are investigated and calculated. The heat load generated by resistive wall wakefields is considered as well. Results are presented for power losses of every element in the 1.3-GHz cryomodule, caused by HOM excitation in the acceleration RF system of the continuouswave linac of SHINE. 展开更多
关键词 Power loss HIGHER-ORDER MODES (HOMs) Resistive wall WAKEFIELDS Impedance SUPERCONDUCTING CAVITIES
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Effect of Nb addition on the microstructural,mechanical and electrochemical characteristics of AlCrFeNiCu high-entropy alloy 被引量:7
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作者 N.Malatji A.P.I.Popoola +1 位作者 T.Lengopeng S.Pityana 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2020年第10期1332-1340,共9页
AlCrFeNiCuNbx(x=0.05,0.15,and 0.26)high-entropy alloys(HEAs)were successfully fabricated using the laser metal deposition technique.The laser power of 1600 W and scanning speed of 1.2 m/min were used during laser proc... AlCrFeNiCuNbx(x=0.05,0.15,and 0.26)high-entropy alloys(HEAs)were successfully fabricated using the laser metal deposition technique.The laser power of 1600 W and scanning speed of 1.2 m/min were used during laser processing of the alloys.The microstructural,mechanical,and electrochemical characteristics of the alloys were evaluated using various advanced characterization techniques.Results showed that the alloys exhibited a dual-phase structure with dendritic grains.The inclusion of Nb in the AlCrFeNiCu alloy matrix promoted the formation of fine eutectic structures and changed the shape of the grains from columnar to equiaxed.The Cu content decreased with the increase in the content of Nb,whereas the Al content increased with the increase in the content of Nb.The findings indicated that the presence of Nb in the alloy promoted the formation and enhanced the stability of the body-centered cubic(bcc)phase.All of the alloys that contained Nb also exhibited high hardness,compressive strength,and wear resistance.Furthermore,the low current density and positive shift in potential exhibited by HEAs with appropriate addition of Nb highlighted the superior anticorrosive properties. 展开更多
关键词 high-entropy alloys microstructure MICROHARDNESS FRICTION wear loss corrosion resistance
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Mechanism of Strength Loss of No-bake Phosphate Bonded Sand Mold/Core 被引量:1
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作者 张友寿 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2009年第1期5-8,共4页
The strength loss mechanism of the phosphate bonded sand mold/core was studied. The morphology and composition of phosphate membrane on the surface of sands was analyzed with electron probe X-ray microanalyzer. Result... The strength loss mechanism of the phosphate bonded sand mold/core was studied. The morphology and composition of phosphate membrane on the surface of sands was analyzed with electron probe X-ray microanalyzer. Results show that magnesium causes cracks in cured phosphate membrane and results in the decrease of sand molds/cores strength. However, the addition of magne-sium significantly enhanced hygroscopy resistance of phosphate membrane. In addition, the phosphate binder added with the magnesium modifier has more rapid hardening reaction speed compared that without or with low magnesium binder. It can be concluded that the phosphate binder with the addition of magnesium modifier is favorably used in high humid and cold circumstance. 展开更多
关键词 PHOSPHATE mechanism of strength loss CRACK hygroscopy resistance
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Pediatric obesity prevention:From na?ve examination of energy imbalance towards strategies that influence the competition for nutrient resources among tissues 被引量:2
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作者 Lynae J Hanks Tina Simpson +1 位作者 Kenneth McCormick Krista Casazza 《World Journal of Clinical Pediatrics》 2015年第4期50-54,共5页
Current pediatric obesity interventions have collectively yielded relatively unsuccessful results. In this Field of Vision, we present plausible physiologic underpinnings fostering ineffectiveness of conventional stra... Current pediatric obesity interventions have collectively yielded relatively unsuccessful results. In this Field of Vision, we present plausible physiologic underpinnings fostering ineffectiveness of conventional strategies grounded in requisite induction of negative energy imbalance. Moreover, such recommendations exacerbate the underlying metabolic dysfunction by further limiting metabolic fuel availability, lowering energy expenditure, and increasing hunger(recapitulating the starvation response amid apparent nutritional adequacy) which precede and promote obesity during growth and development. The qualitative aspects of musculoskeletal system(i.e., endocrine response, muscle functional capacity) are likely to improve metabolic function and increase nutrient delivery and utilization. An intricate and complex system including multiple feedback mechanisms operates to homeostatically regulate energy balance and support optimal body composition trajectories and metabolic health, during growth and development. Thus, ignoring the interdependencies of regulatory growth processes initiates a nuanced understanding of energy regulation and thus misguided attempts at preventive strategies. Importantly, these gains are not dependent upon weight-loss, rather we suggest can be achieved through resistance training. Collectively, optimizing musculoskeletal health via resistance training elicits augmentation of competitive capacity across systems. Further, substantial gains can be achieved in skeletal muscle mass, strength, and functional capacity through resistance training in a relatively short period of time. 展开更多
关键词 CHILDHOOD obesity Metabolic control ENERGY balance resistance training Effective intervention STRATEGIES Weight loss MUSCULOSKELETAL health
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New Li-ion Battery Evaluation Research Based on Thermal Property and Heat Generation Behavior of Battery 被引量:1
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作者 Zhe Lv Xun Guo Xin-ping Qiu 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2012年第6期725-732,I0004,共9页
We do a new Li-ion battery evaluation research on the effects of cell resistance and polariza- tion on the energy loss in batteries based on thermal property and heat generation behavior of battery. Series of 18650 ce... We do a new Li-ion battery evaluation research on the effects of cell resistance and polariza- tion on the energy loss in batteries based on thermal property and heat generation behavior of battery. Series of 18650 cells with different capacities and electrode materials are evalu- ated by measuring input and output energy which change with charge-discharge time and current. Based on the results of these tests, we build a model of energy loss in cells' charge- discharge process, which include Joule heat and polarization heat impact factors. It was reported that Joule heat was caused by cell resistance, which included De-resistance and reaction resistance, and reaction resistance could not be easily obtained through routine test method. Using this new method, we can get the total resistance R and the polarization parameter U. The relationship between R, η, and temperature is also investigated in order to build a general model for series of different Li-ion batteries, and the research can be used in the performance evaluation, state of charge prediction and the measuring of consistency of the batteries. 展开更多
关键词 Li-ion battery Energy loss HEAT Cell resistance POLARIZATION State of chargeprediction
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Experimental Determination of Local Resistance Coefficient of Sudden Expansion Tube
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作者 Yinpeng Li Changjin Wang Mingda Ha 《Energy and Power Engineering》 2015年第4期154-159,共6页
Theoretical derivation of local resistance coefficient of sudden expansion tube is presented. Several assumptions are analyzed in the theoretical derivation. That the head loss shall be neglected is affirmed. Experime... Theoretical derivation of local resistance coefficient of sudden expansion tube is presented. Several assumptions are analyzed in the theoretical derivation. That the head loss shall be neglected is affirmed. Experimental data proves that the pressure before and after sudden expansion section is basically the same. That the friction force on the side face of control body is neglected is denied and it is pointed out that such neglect is the main cause for error between theoretical calculation and actual measurement. Experimental device for measuring local resistance coefficient is designed in combination with theoretical derivation process. Optimal gradually varied flow section is selected after sudden expansion pipe in Bernoulli equation based on variation of piezometer tube head. It is pointed out in accordance with experimental data analysis that the value of local resistance coefficient of sudden expansion tube determined through experimental data is closer to the actual situation during pipeline design. 展开更多
关键词 SUDDEN EXPANSION PIPE Frictional HEAD loss loss HEAD loss Local resistance COEFFICIENT
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